The present invention relates to a liquid crystal display apparatus, and particularly relates to a liquid crystal display apparatus provided with a plurality of pixels.
Since a liquid crystal display apparatus has such features as light weight, compact size and low power consumption in comparison with a CRT (Cathode Ray Tube), it is used in various types of electronic device as a display. A liquid crystal display apparatus displays an image by changing an orientation of liquid crystal molecules aligned in a predetermined direction by an electric field and controlling the amount of light transmission through a liquid crystal layer.
A liquid crystal display apparatus has a pair of substrates including, for example, an array substrate and a color filter substrate. In the array substrate, for example, thin film transistors (TFTs) as switching elements are formed in an array so as to correspond to each of the pixels of the liquid crystal display apparatus. In the color filter substrate, color filters are formed so as to correspond to each of the pixels of the liquid crystal display apparatus. A space between the array substrate and the color filter substrate is filled with a liquid crystal layer, and an electric field applied to the liquid crystal layer is changed by switching the TFT in each pixel.
As a method of applying an electric field to a liquid crystal layer, the method utilizing a vertical electric field scheme and the method utilizing a lateral electric field scheme have been known.
In the liquid crystal display apparatus employing the lateral electric field scheme, for example, on a liquid crystal layer side of either one of a pair of substrates including an array substrate and a color filter substrate, a pair of electrodes is provided so as to be insulated from each other, and an approximately lateral electric field is applied to the liquid crystal molecules. As the liquid crystal display apparatus employing the lateral electric field scheme, the apparatus of an IPS (In-Plane Switching) mode in which the pair of electrodes is not overlapped with each other when seen in a plan view and the apparatus of an FFS (Fringe Field Switching) mode in which the electrodes are overlapped with each other have been known.
Of these, in the liquid crystal display apparatus of the FFS mode, paired electrodes including a common electrode and a pixel electrode are each disposed on respectively different layers via an insulating film, a slit-like aperture is provided in the common electrode or the pixel electrode on the liquid crystal layer side, and an approximately lateral electric field passing through this slit-like aperture is applied to the liquid crystal layer. Since the liquid crystal display apparatus of the FFS mode has such effects as wide viewing angle and improved image contrast, it has been used more in recent years.
As the liquid crystal display apparatus of the FFS mode, the apparatus in which a common electrode and a pixel electrode are both disposed on the array substrate and above TFTs has been known. In the liquid crystal display apparatus with the structure like this, surfaces of the TFT and others are covered with an interlayer resin film in the array substrate, and a lower electrode made of a transparent conductive material and an upper electrode having a slit-like aperture are formed on the surface of the interlayer resin film with interposing an inter-electrode insulating film therebetween.
On the other hand, in the part between each of the pixels on the liquid crystal layer side of the color filter substrate, a light shielding portion is formed. Japanese Patent Application Laid-Open Publication No. 2011-164369 (Patent Document 1) and Japanese Patent Application Laid-Open Publication No. 2011-27951 (Patent Document 2) describe the technology of forming a light shielding portion at a position on a color filter substrate opposed to a scanning line and a signal line in the liquid crystal display apparatus of the FFS mode.